Controlling device for electric motors.



PATENTED APR. 23, 1907.

J. D. IHLDER.

CONTROLLING DEVICE FOR ELECTRIC MOTORS.

APPLICATION FILED SEPT. 27, 1904.

W/TNESSES UNITED srArEs PA'rEN'r oEEIoE;

JOHN `rD. IHLDER, OF YONKERS,'N EW YORK, ASSIGNOR TO OTIS ELEVATOR COMPANY, OF JERSEY CITY, NEW JERSEY, A CORPORATION OF N EW i JERSEY.

CONTROLLING DEVICE FOR ELECTRIC MOTORS.

Specification of Letters Patent.

Patented Apri1'23, 1907.

Application led September 27, 1904. Serial No.v 226,116.

To all, whom t may concern.-

Be. it. known that I, JOHN D. IHLDER, a citizen of the United States, residing at Yonkers, in the county of Westchester and State 5 of New York, have invented a certain new and or excessive speed for electrically retaiding zo' or impeding the operation of the motor.

Other objects of theinvention will appear more fully hereinafter. The invention consists substantially in the construction, combination, location and relative' arrangement of parts, all as will be more fully hereinafter set forth, as shown in the accompanying drawing, and iinally pointed out in the appended claims. Referring to the accompanying drawing, and to the varioi's views and reference signs appearing thereon,-Figure l is a view in.

diagram showing one form in which my invention may be a plied to the control of an 'electric motor. Figs. 2, 3, and l illustrate modifications of details.

The'same part is designated by the same reference sign Wherever it occurs throughout the several views. f

.'In the operation of electric motors and particularly motors which are required to operate under frequently varying conditions of load, as, for instance, in the-special lield of electric elevators, the motor sometimes. attains an undue or excessive speed. This is particularly. true in the case ormotors employed in electric elevator service when the motor is'driv'en by the load and thereby bef comes a generator.

It is among the special purposes of my present invention to provide means which are simple ,efficient and automatic in operation for im- 4posing a retarding influence upon the motor.

his object may be accomplished in manyA speciically different ways, as by applying an ,i e

ectro-dynamic brake to the `motor, by strengthening the magnetic field of' the motor, or by breaking the motor circuit and thereby stop ing the motor, or by combining these severa methods, and in carrying out my invention I pro ose to provide means operated automatica ly when the motor at-V tains an undue or excessive speed for accomplishing the objects and purposes stated.

It is obvious that my invention may be applied to many different 'styles and types of motor and accessory devices for starting, stoppig, reversing and controlling the motor. iile, therefore, I have selected for purposes of illustration a certain type of motor and controllin devices therefor, I desire it to be understooi-l tobe limited or restricted thereto, as variations therefrom and changes therein would readily suggest themselves to ersons skilled in the art Without departure rom the spirit and scope of my invention and without aithat my invention is not ecting the objects and purposes attained by my invention or the cooperative operation thereof.

In thel drawing reference sign 20, designates a motor, 2l the armature thereof,22, 23 its brushes, .50 ieldcoils, 4() a resistance, the field coils 50 and resistances 4() designed, in starting up the motor, to be included in series with the armature, and 100 designates the shunt field coils.

Any suitable arran ement and construen tion may be employe for successively cutti out or short circuiting the resistances 4 0, arid the series fieldI coils 50, as the motor slpeeds up. I have selected for purposes ot' ilustration one form of mechanism for'accomplishing this result, to which, however, my invention is not to be limited or restricted, and comprising a ma net 30, the coil 3l of which is included in a s unt circuit 27, 28, across the brushes ofthe motor. By this arrangement it will be readily seen that as the motor accelerates the strength of magnet 30 increases, and as the strength of said magnet increases it may be employed to successively cutout or short circuit the startingresistance 40, and the series field coils, as, for instance, by successively attracting the contacts 39, 38, 37 and 36, to contacts 35, 34,33 and 32, in a Well understood manner.

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Any suitable form, construction and are;

rangement of starting, stoppinv and reversing switches may be employed. bWhile, theretore, i have selected for purposes oi illustration simple construction of switches, and which have found in ractice to be well adapted for the purpose, desire it to be understood that vmy invention is in no wise to Wire 16. The coils of ma nets 91, 92, are respectively included in circuit on one side t rough wires 18 and 17, with contacts 13 and 14, and on the other side through wire 95, to the negative main 5. The magnets 91, 92 control a reversing switch, and which as Aabove indicated may be of any suitable form or construction. In the form selected for purposes of illustration this switch comprises a lever 80, pivoted as at 81, and to which are connected as at 88, the cores 89, 90, of magnets 91, 92, respectively, so that said lever may be rocked or swung inone direction or the other according as one or the other of magnets' 91, 92, is energized. The lever 80, includes suitably insulated conducting parts 82, 83. The part 82 o erates to bridge contacts 87 and 56, when ever 50 is rocked in one direction, and to bridge contacts 77 and 55, when said lever is rocked in the other direction.. Similarly, lpart 83 serves to bridge contacts 85, 86, or 84, 7 8, ac-

cording to the direction in which lever is rocked. Contacts 85, 84, are connected together electrically and also .to the positive main 7.l Contacts 77 and 86 are electrically connected together,- and, through wire 25,to the motor brush 23, while contacts -78 and 87, are electrically connected, and, through wire 26, to the motor brush 22. The contacts 56, 55, are connected together, and through Wires 54 and 51, are in series with the series eld 50, resistances 40, and Wire 41, to the negative main 5; The shunt field 100 is connected on one side through wire 102 with the positive main 7, and on the other side through Wires 101 and 41, to the negative main 5. If desired, the reversing switch lever 80, may be held in central position in any convenient manner, as, for i-nstance, by means ofthe springs93, 94.

lThe parts so far described and referred to and as above indicated, maybe of any suitable construction and arrangement, and in the s eciicccnstruction and arra ementof the etailsthereof form noiart o my present invention, being selecte merelyor purposes or illustration and as showing structions and arrangements which y conhave found practical and efficient in operation and in cooperation with my present invention,"

in carrying out my ciation' with a motor and accessory devices oi the general nature above referred to and as indicated,'ll propose to provide means whereby the `niotor may be automatically slowed down'or stopped upon attaining an undue or excessive speed, and it is obvious that this result rmay be accomplishedin .many specifically different ways.

in ,one form ci embodiment of my invention i pro ose to apply an electro-dynamic brake, an this I acomplish by automatically completing a shunt circuit across the armature and 'in which circuit is placed resistance, and I propose to complete this shunt `circuit automatically b the undue or excessive speed developed y the motor or by the current generated by` the motor when it i's'runas a generator.' this means oi accomplishing the desired object, I have shown a resistance 79, connected on one si'de to contact 78, and on the other side through wire 76, to a contact 66. A cooperating contact 68 is connected through wire 75, to contact 77.

as a magnet 60, arranged to be properly and suitably energized sufficiently, when the motor attains an undue or excessive speed,

or becomes a generator, may be used to close the circuit between contacts 66 and 68. Theresistance 79, when its circuit is closed, thus forms in effect an electro-dynamic brake and its tendency is to slow down the motor.

V1n another form of embodiment of my invention I propose to provide means operated automatically, when the speed of the motor unduly .increases or becomes excessive, or

invention and in assoo illustrate This shunt circuitA is normally open between contacts 66 and i 68. Any suitable means, such, for instance,

when lthe motor becomes a generator, for

strengthening the magnetic fieldof the motor. This result may be accom lished in many specifically diiierent ways. o illustrate one form of means sult, I have shown an extra shunt iield' Winding 103, the circuit of which is connected on one side throu h wire 102, in shunt with the armature 21 o? the motor,and onthe other side through wires 104, 106 and 73, with a contact 67. If desired, there may be included in this circuit a resistance, indicated at The contact 67 is'normallyse afor accomplishing thisl rerig,

rated from a cooperating-contact 69, whic is 'connected through wire 74, to wire 51, and hence when this circuit isA closed through contacts 67, 69, an auxiliary shunt eld circuit is established -in which is included auxiliary field coils, thereby strengthening the magnetic ield of the motor and hence tending to impede or .retard the speed thereof.' The contacts 67 69, may be closed upon each other in any suitabiemanner, as, for

speed of t instance, by magnet 60, arran ed, as above indicated, to be automatica ly energized sufficiently when an undue or excessive e motor is attained.

If desired, the methods above described of applying yanelectro-dynamic brake and of strengtheningthe magnetic field of the motor in theaccomplishment of the objects of my invention, may be combined in their action, or may be carried out at the same time, as, for instance, by connecting both contacts 66 and 67, through insulation 70, and a rod 72, with the core armature 7l, of ma net 60, any suitable arrangement being emp eyed to maintain the contacts 66 and 67 normally separated from their` respective cooperating contacts 68 and 69. In one arrangement 'for accomplishing this result I employ a spring 64, secured at one end at 65, and connected at the other end to the rod 72, the 'tension of said spring operating to normally maintain contacts 66 and 67, and their cooperating contacts 6.8 and 69, separated until magnet becomes sufiiciently energized to overcome such tension.

l have illustrated in Fig. 2 another arrangement. embodying the princi les of my invention, wherein the circuit of 51e motor may be automatically broken by including contacts 68, and 69 in a convenient part oi the motor circuit, and normally maintaining such circuit closed by means oi cooperating electric ally connected contacts 66 and 67. in this case the energization of magnet 66 to a sufi'icient extent will break the motor circuit by separating the contacts 66 and 67', respectively, from contacts 68', 69.

li desired, ail three methods 'above de scribed may he combined; That is, the elec-- tro-dynamic brake may be applied, the inagnetic `iield of the niotor may be strengthcned, and thel circuit of the motor broken in successive order, and in Fi.; 3 l. have iilustrated a means for accomplishing this cornbined result, wherein two magnets 6U are associated, one designed to eifect therst tivo steps, and the other the final step of the oneration, said magnets being so relatfve y wound and adjusted as to properly these functions. f

in the foregoing description have re- `crfed the magnet v6() as being suiiiciently energized when the motor attains an undue or. excessive speed or operates as a generator, to eiicct the operation explained. To this end, the coil 62, ci' magnet 60, may i, ne eluded; in a shunt circuit across the n armature and so relative-lv Wound as to i proper or suilicient energization oi the inegnet only when the motor attains au undue or excessive speed or o crates as a generator. This arrangement is illustrated in Fig. 4.

Another and a preferable way is shown in Figs. 2 and 3, wherein the nmgnct is provided with oppositcly wound coils` 62, and 53. rThe magnet may therefore be termed 'a doubly wound magnet or a differential magnet. The coil 53 is included in series with the armature circuit or the motor, while the coil 62 is included through wires 63 and 61, in a shunt circuit around the motor armature. Under these conditions it will be observed that the energizing cil'ccts of theseicoils upon magnet 60 tend to counterbalance or neutralize each other when currents are flowing through the circuits of said coils. The energizingeilect ol" coil 62, however, will vary with the variation of not-critici' at the armature brushes, since sain coil is shunted across the armature, and the energizing eilect of the coil 53 will vary with the current through the armature and consequently when the potential across the brushes suiiiciently increases by the atl taimnent of an undue or excessive speed, the

'overl'salancing or neutralizing eiiect of coil 53 is overcome and magnet 6() will become suiliciently energized to accom lish the objects and purposes alcove set Orth. In l, other words, the coils tend to neutralize each other and the magnet comprising said coils becomes suiiciently strong to operate its switch only when the difference in the strengths of these coils becomes great enough. @rdinaril y the saine time that the coil 62 strengthens the c il 53 vveahens, thus increasing the oiiierential action oi the entue magnet.

in case the motor becomes e generator so that it sends current bach into the line, then the new oi cuire t throuch coil 53 will comcnw eine in n that through coil 62,

tne saine res will he secured.

'lt is believed t the operation will be fully 1 toed from' the foregoing description, out or the salie ci cleerness will be briefly described.

Suppose contact l2 is moved into contact with contact c. circuit is thereupon established, follows:

i6, contact if?, ce

'oni positive main 7, wire I t i3, Wire i8, nie-.guet 9i., wire 95, neg ve rhein 5. The resultmagnet results in rockinc1 enercizaticn or b D ,L I, ing lever 8'() to the iA t thereupon completing thefollovving circuit: .trom positive main 7, to

contact 9,5, contact o,.contact wire 25, brush 23, ern'iature 2l, brush 22, wire 26, contact 87 contact 82, contact 56, wire 54, coil 53, 'vf 'es Jiield 50, resistance 40, wire 4l, ina-in. 5. The shunt field circuit from positive main 7, through vire l, cunt iield 106, wire i'l Wire l negative main 5. The moall the subsequent op.,

c. is the motor eccelsfil, and the series held l f out out, the circuit hecessivc speed or should it becomea generator, magnet 60 becomes energized suffilll ' COTIIGS ii cientl to cause contacts 66 or 67, or both, toi' comp ete circuit connection with contacts 68 v and 69, respectivel thereby 'com loting a shunt circuit aroun the armature om contact 86, through contact 77, wire 75, contacts 68, and 66, Wire 76, and resistance 79,` to contact 78 and contact 87. The closing of contacts 67 and 69, closes the auxiliary field circuit from Wire 51, through Wire 74, contacts 69 and67, wire-73, wire 106, resistance 105, Wire 10c, and auxiliary field coils 163, to the shunt iield circuit `wire 3.02, and thence on to the positive main 7. 0r the enervisation of magnet 66 operate toair the motor circiiit as indica *ed in 2, ci to combine the several methc described in Fig. 3.

l have above traced the circuit when the contact 12 is moved position to close the circuit through contact l/Vhen said contact l2 is moved. to close circuit through contact it, the circuit oi magnet 92 is completed, and hence the lever 80 is rocked towards vthe right. The only difference resulting is that the circuit through the motor armature is reversed. K

l-lavin'g now set forth the object and nature of in invention, and various construcy. tions an arrangements for accomlishin suoli obyects, Whatl claim as new an usefu and of myown invention, and desire to secure by Letters Patent, is:

l. The' combination vwith a compound- -Wound motor, oi means entirely electrical for reducing the speed of the motor, and means made operative by undue or excessive speedoi the motor and when said motor beenerator Vfor bringing into action said s eed reducing means.

2. he combination with a motor, ci' an auxiliar iield circuit, resistance in said auxiliary fie d circuit, and means made operative by an undue speed of themotor for closing said circuit.

3. The combination with a compound Wound motor, ot an additional field circuit,

.excessive speed of the motor for and means made operative 4by an undue or inserting said additional iield circuit.

e. The combination With a compound Wound motor, of an additional field circuit, resistance in said circuit, and means made o erative b an undue or excessive speed of t emotor or inserting said additional field circuit. l i 4 f 5. Thecombination with a motor, of an auxiliary shuntfleld circuit for said motor, and means made operative by an undue speed of the motor for closing said circuit` 6. The combination with a compound- Wound motor of an additional shunt field circuit for said motor,and means made oper-l ative by an undue s eed ofthe motor for connecting1 said additional circuit in parallel with the s unt Winding of the motor.

7. The combination l`With 4a compoundwound motor, of anadditional shunt field circuit for said motor, 'resistance in said additional circuit, and means made operative by an undue speed of the motor for connecting said additional circuit in parallel with the shunt winding of the motor.

8. The combination with a motor, of a dynamic brake and an auxiliary eld circuit therefor, and means made operative by an undue or excessive speed of the motorfor eifecting the operation ci said dynamic brake and the closure oi said auxiliary field circuit.

Q. rl`he combination with a motor, of an auxiliary iield'circuit for saidJ motor, a normally o en circuit in shunt to the motor-armeans made operative by exce sneed ci the motor for ccmpici.. said field circuit and for completing said shunt circuit.

The combination with a compound- Wound motor, ci devices Wholly electrical for reducing the speed of the motor, and means made operative by undue or excessive speed of the motor and when said motor becomes a generator for bringing into action said electrical devices.

l1. The' combination with a compoundf Wound motor, of means entirely electrical for reducing the speed ol' the motor, and electrical devices made operative by the undue or excessive speed oi t e motor and when the motor becomes a generator for bringing into action said speed reducing means.

12. The combination with a compoundwound motor, of electrical devices for reducing the speed ofthe motor, and electrical dcvices made operative by undue or excessive speed of the motor and when said motor acts as a generator for bringing into action said speed reducing devices. A

13. 'The combination with a motor, of an electro-dynamic brake, circuit, and means operated by undue or excessive speed ci the motor and upon conversion of the same into IOC a generator for varying said circuit to effect a reduction of speed of said motor.

, lli. rl'ihe combination with a motor, of means for strengthening the ma etic field of the motor, by adding extracoi s and moans dependent upon the armature potential and made c erative by the undue or excessive speed o the motor for making effective said field strengthening means.

15. The combination with a motor, of means dependent upon the armature current and made operative by the undue or excessive speed of the motor for strengthening the magnetic field of the motor.

16. The combination with a motor, of an auxiliary field circuit for said motor, and means made o erative by an undue speed of the motor foi c osing said circuit.

.in shunt to the motor, an auxiliar riielcl circuit, and means made operative y the excessive speeds of the motor for completing said circuits.

'20. The combination with a motor, of a circuit therefor, a circuit breelrer arranged therein, an electro-dynamic brake, a circuit therefor in shunt to the motor, and means made operative by excessive speed of the rnctor for com leting said brake circuit and op# l erating sai circuit breaker in succession.

:31. The combination with a motor, circuit therefor, a circuitbres-iter arranged. therein, an electro-dynamic brake, a shunt circuit therefor, an auxiliary shunt iield cir cuit, and means made operative by excessive speed of the motor for completing said auxiliary iield and iiralie circuits and onere-.t said circuit breaker in succession. h

22. The combination withd a motor, electro-dynamic brake comprise o independent of the iield circuit oi said l end e magri-etto eiiect the application such brake to the motor, and means in energizing such magnet when ai of tire motor is rotated et lexcessive spec".

23. The combination with rector, electric retarding device comprising; a iield Winding for such motor, magr eiiectino" the application oi such re device, :but of insuiiicient strength tv., ergizecl by the normal current through the motor, and means f excessive speed ci' the version ot the same into gestrongly energising said magnet its function.

The combination with source of electrical supply, a re for the motor, a magnet for apply tarding device having two Wind which is directly connected acres ture oi the motor and neutraiizes the etreeAL the other when the motor is receivi'i from the source ci supply, the other'when the motor is rent. f

25. 'The combination with :ci

rcsistan'ce, circuits and contacts ci to connect said resistance across the ern `cre of the motor, and a magnet for controiiing said contacts, said magnet only having sui cient strength to attract its armature and move its contacts When the motor armature has excessive speed.

26. The combination With a motor having an armature and a shunt field, a resistance, an extra shunt field, circuits and contacts arranged when closed to connect said resistance across the armature of the motor, and to energize the extra shunt iield, and a magnet which closes said contacts whenever the speed of the motor gets excessive. l

27. The combination with a motor, of a resistance, circuits and contacts arranged to connect said resistance across the armature of the motor, and a magnet havingits terminals connected directly across the armature and arranged to control said contacts to effect a reduction of speed.- of the motor when said speed becomes excessive or to eiiect a reduction of the speed of the motor upon conversion oi the same into a generator.

2S. rifhe combination with a motor, con-- trolling apparatus therefor, a doubly wound magnet having one winding in circuit with the motor-armature and lthe other Winding connected across the inonir-armature, and electric means controlled by said magnet for regulating the speed of tlie motor.

29. The combination with a motor, oi' controlling i'ipparatus therefor, a differentially Wound magnet having one Windin f connect ed. across the motor-armature an another Winding in circuit with the motor-ar1nature; and electric means controlled by said magnet 'for slowing down said motor when excessive speed is attained, or upon convcrsi n oi the into s. generator.

Si). rlie combination with motor, or starting means therefor, a differentially Wound relay having' one Windin f connected across the inotf r meters and the other winding in series th the motor-erin electro-dynamic brake circuit, sud controlled by said relay for closing said circuit when the motor acts as a general Si. The combination with a motor, ci reversing switches tnerejior, a diierenti "M" having one Windin connected acres motor-armature and the other inding in c rrnelly open circuit Wits. the motor-erniature, controlled by said relay for regulatine the speed of seid motor, ines for operating said r Jersing switches tcc rinelly open circuit and efiect he motor i'o the desired direction.. rhe cornbin "on vzfith a motor, oA

' eier, a doubly we foleraiity ci resiste means controlled by s id electroun ertingv one et? said resistances ocal circuit in seri with the motor ure, and another oi resistances in shunt "o the motor.

33.' The combination with an electric motor, ci controlling apparatus therefor, a doubly wound magnet, two-resistances, an

con-

IOO

'trolling apparatus therefor,

extra eld coil for the motor, and'means controlled by said'mavnet for inserting Oneof said resistances in allooal circuit in 'series with the' motor-armature and the other with said i eX-tra field coil in, shunt to the motor when the motor acts as a generator.

i 34. The 'combination With-a motor, of cona .differenti al relay, and means comprising a circuit independen'toi theeld circuit, and controlled by said 'relayfor effecting a stopping ot said motor when the same acts as a generator.

B yThe combination with a motor, of means entirely electrical and comprising a circuit independent ci the iield circuit for reducing thefspeed oi the motor, and means made operative by undue or excess fe speed 'e motor "for l t; into eenen ientially Wound magnet having one winding connected directly across the motor armature and another winding in circuit with the moesmas tor armature; and electric means controlled by said magnet for slowing down said motor when excessive speed is attained, or upon conversion of the same into a generator.

38. The combination with an electric mo- 'tor, of reversing switch apparatus therefor, a

differential relay havin one windingy connected directly across t emotor armature and lthe other winding in a normally open circuit with the motor armature,` and means controlled by said relay for limiting the speed of said motor.

39. The combination with an electric mo tor, of controlling apparatus therefor comprising reversing switch mechanism and accelerating mechanism, an. electro-dynamic brake circuit normally open, and two didiern ential relays one controlling the toi.- circuit and the other. controlling both the electro-dynamic brake .circuit and said extra iield circuit, one ot the windings oi each ci' said relays being arranged 'to be connected in circuit withthe motor armature, and the.

other winding of each ot said relays being connected across the motor armature.

in testimony whereof, l have hereunto set 'my hand this 24th day of Se tember, i904, in the presence of the subscri ing witnesses. l JHN D. lljllJlDElt.

Witnesses:

W. Sronns, Pinatar limsi-. 

